In the International Telecommunications Union-Telecommunication Standardization Sector (ITU-T) that currently standardizes Operations, Administration and Maintenance (OAM) of a next-generation Passive Optical Network (PON) system, G.988 (namely, a common Optical Network Unit Management and Control Interface (OMCI)) is being standardized as a next version of G.984.4, namely an existing OAM standard. In particular, G.988 may define OAM that may be used in common in the Gigabit PON (GPON) and the Ethernet PON (EPON). In the G.988 standard, an OAM packet with a fixed size of 53 bytes used in G.984.4 may be changed to have a variable packet length up to 1980 bytes, so that an OAM message may be transmitted and/or received.
However, in G.988, a packet transmission and reception rule of using an OMCI message of a fixed size that has been used in G.984.4 is applied without any change, and accordingly there is only a difference in that an OAM message with a variable length is simply transmitted.
Accordingly, since an OAM packet that may be transmitted up to 1980 bytes is used within ‘48±α’ bytes despite using a variable length applied to G.988, actually there is no efficiency obtained by applying the variable length. Additionally, since a similar number of OAM packets is transmitted or received during activation of an Optical Line Terminal (OLT) and an Optical Network Unit (ONU), there is actually no difference in time due to the activation of the OLT and the ONU.
For example, in a difference in transmission rate based on a windows size of a Transmission Control Protocol (TCP) transmission mechanism that is being used in the Internet, the transmission rate may increase as the windows size increases. Accordingly, in G.988, it is possible to increase a transmission rate and efficiency, by exchanging OAM messages using the entire 1980 bytes, rather than exchanging OAM messages within ‘48±α’ bytes.